package javaBase.nowcoder.HJ34_B_图片整理;

import java.io.*;
import java.util.Arrays;

public class Main {
    public static void main(String args[]) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String str = br.readLine();
        char c[] = str.toCharArray();
        Arrays.sort(c);
        System.out.println(c);

    }
}
